A while back, someone who had the publishing rights for a lot of old songs began threatening a lot of online lesson providers with legal action because they were using 'their' music in their lessons.

Ben had to, at least temporarily, remove a few songs while he works out the legal implications.

Can't help with the Mumford tune but their banjo parts don't seem too complicated but are fast. So you need to be very familiar with your banjo to play this stuff easily. It's mostly like playing really fast backup. This sounds easy but I've been at this for four years now and am just getting there...

Though you won't be able to play along with any recordings of the song, if you don't want to completely retune the banjo to play the tab, just spike the 5th string to A (7th fret).

Like I said, this is all about playing really, really fast and in time. This just means that you are so used to playing that you don't need to think anymore about what you are doing and you just do it kind of automatically.